Monoazo compounds



Patented Dec. 20, '1949 STATES PTENT -FF-ECE MONOAZ O COMPOUNDS JosephB. Dickey, Rochester, N. Y., 'assignor to :Eastman .Kodak Company,Rochester, N. :Y., a

corporation of New Jersey No Drawing. Application April 5, 1945,SerialNo. 586,831

2 Claims. 1

This invention relates .to new azo compounds having the formula:

hydroxyalkyl NO N=N stitute valuable dyes for the coloration of textilematerials such 'as'organic derivatives of cellulose, wool, .silk,.nylon, and .vinyl acetate-vinyl chloride copolymers textile materials.They are particularly of value for the coloration of cellulose acetatetextile materials. Lacquers composed of cellulose esters, cellulose=e'thers and vinyl derivatives, for example, also can be colored.Coloration can be efie'cted by dyeing, printing, stenciling or othersuitable means.

It is an object of my invention to provide a new class of 'azo dyecompounds. Another object of my invention is to provide a process forthe coloration of organic derivatives of cellulose, wool, silk, nylon,and vinyl acetate-vinyl chloride copolymers textile materials. A furtherobject is to provide colored textile materials which possess goodfastness properties. A specific object .is to provide colored celluloseacetate textile materials which have good fastness properties. Otherobjects will appear hereinafter.

Typical organic derivatives of cellulose include the hydrolyzedas wellas the unhydrolyzed cellulose organic acid esters such as celluloseacetate, cellulose formate, cellulose propionate or cellulose butyrateand the hydrolyzed as well as the unhydrolyzed mixed organic acid estersof cellulose such "as cellulose acetate-propionate, celluloseacetate-butyrate and the cellulose ethers .such .as methyl cellulose,ethyl cellulose or 'benzyl cellulose.

.The vdyeings obtained with the .dye compounds of my invention arecharacterized by excellent dischargeability, excellent .fastness tolight and to gas 'fumes and by good fas'tness .to washing andperspiration. Further, the dye compounds possess good afiinity for thetextile materials named, especially cellulose acetate textile materials,and can be applied rapidly thereto at relatively low temperatures. Theadvantages of the dye compounds appear to be realized to their greatestextent when cellulose acetate is .the material to be colored.

The azo compounds of the invention can be prepared by diazotizing thecompounds having I I NOONH:

wherein X has the meaning previously assigned to it and coupling thediazonium compounds obtained with the compounds having the the formula:

formula:

wherein R has the meaning previously assigned to it.

The following examples will serve to illustrate the new azo compoundsand the manner of obtaining the same.

Example 1 7.6 grams-of sodium nitrite (dry) were added slowly withvigorous stirring to cc. of sulfuric acid (-96%). The resulting mixturewas stirred until a clear solution of :n'itrosyl sulfuric acid wasobtained. The solution was cooled :to 12 C. to 14 C. and 120 grams ofglacial acetic acid were added with stirring. 20.6 grams of 1- amino '2"trifluoromethyli-initrobenzene and grams of glacial acetic acid were"added to the mixture simultaneously with stirring at 15 'C. Stirring at15 C. was continued for two hours. "The resulting di'azo solution waspoured into 1000 grams of ice and the resulting iced solution was addedto an :iced solution of 2253 grams of N ethyl -N pw-dihydroxypropylmethylaniline in dilute hydrochloric acid. The coupling reaction whichtakes place was completed by adding sodium bicarbonate until the mineralacid was practically neutralized. The dye compound formed wasrecoveredby filtra- 3 tion, washed with water and then dried. It has theformula and colors cellulose actetate textile materials brownish-redfrom its finely divided dispersions in water.

The following tabulation further illustrates the compounds includedwithin the scope of my in- CHzCHOHCHzOH vention or discovery togetherwith the color they on yield on cellulose acetate. Generally similar andcolors cellulose acetate rayon textile mateshades are produced on theother textile materials rubine shades from its aqueous suspensions.rials indicated hereinbefore. The compounds indicated below may beprepared by diazotizing the Example 2 24 grams of1-amino-2-trifluoromethyl-4- nitro-B-chlorobenzene were diazotized andthe diazonium compound resulting was coupled amines listed under theheading Amine and coupling the diazonium compounds obtained with thecompounds specified in the column entitled Coupling Component.

Amino Coupling Component Color 1 -amino -2-trlfluoromethyli-nitrobenN,N-di- (fl-hydroxyethyl)-3-ethylanil ine rubine N-B-rnethoxyeth-N-fl-hydroxyethy1-3-ethylaniline Do.N-B-cyanoethyl-N-fi-y-dihydroxypropyl-3-ethylaniline Do.. N-CIhCO OCHaN-p-hydroxypropy1-3-cthylanil1ne Do. NCHzCH2COO CHa-N18-11ydroxyethyl-3-ethylanil Do. N -methyl-N-fl,' -dihydroxypropyl-3-cthylaniline brownish-red.

N-CH 0 H2 0 O 0 C zH -N-B-l1ydroxyethy1-3-ctl1ylaniline Do.

N-CH CH2CN-N-fl,' -dhydroxyprlopy1-3-ethylaniline D0.

Do N-n-propyl-N-B-hydroxyethyl-3ethylaniline Do.l-amlno-2-tritluoromethyl-4-nitro-6-N-B-ethoxyethyl-N-B,'y-dihydroxypropyl-B-ethylaniline O- bromobenzene.

o N-fl-hydroxyethylN-'y-hydroxypropyl-li-ethy1aniline Do. DoN-ethyl-N-4,fi-dlhydroxy-n-amyl-3-ethylaniline Do. l-amino-Z-trifiuoromethyl-i-nitro-fi- N,N-di- (fi-hydroxyethyl)-3-etl1ylaniline Do.

fluorobenzene.

o N-n-butyl-N-B,' -dihydroxypropyl-3-ethylaniline Do.1nmino-2-trifluoromethyl-4-I1itro-6-N-isopropyl-N-fi-hydroxyethy1-3-ethylaniline D0.

iodobenzene. I

Do N-CHzCH CN-N-fl,'y-dlhydroxypropyl-B-ethylaniline Do.

l-argino-2,6-di-trifluoromethyl-4-nltr o-N,N-di-(fl-hydroxyethyl)-3-ethylbenzene Do.

enzene. D0 N-CHaCEbC O 0 CzH5--N-fi-hydroxyethyl-3-ethylbenzene D0.

D0 N-OH CH2C O O CHa-N-B,y-dihydroxypropyl-IS-ethylaniline i. D0.

Hz 7 V with 20.9 grams of N,Ndi-(;3-hydroxyethyl)-3 ethylaniline. Thediazotization, coupling and recovery operations can be carried out inaccordance with the procedure described in Ex- It will be understoodthat the foregoing examples are intended to be illustrative and notlimitative of my invention or discovery. The diazonium compounds of anyof the amines inample 1. The dye compound obtained has the dicatedherein can be coupled with any of the formula: couplng componentsindicated herein to yield 01 dye compounds of the invention ordiscovery.

1 011,011,021 In order that the preparation of the azo com- NOON=NON/pounds of my invention or discovery will be V entirely clear thepreparation of certain of the (52115 CHaoHzOH intermediates used intheir preparation will be and colors cellulose acetate textile'materials brownish-red shades from its aqueous suspensions.

Example 3 27.4. grams of 1-amino-2,6-ditrifluoromethyll-nitrobenzenewere diazotized and the diazoniumcompound'obtained was coupled with 25.1

grams of N-fihydroxyethyl N-CI-IzCHzCOOCI-Is- R1 3-ethylaniline. Thediazotization, coupling and recovery operations can be carried out inaccord- C ance with the procedure described in Example 1. hydroxyalkylThe dye'compound has the formula: mm

(JFK CHQCHZCOOCHS wherein R1 stands for a member selected from the groupconsisting of an alkyl group, a hydroxy -Q O K alkyl group, analkoxyalkyl group, and a cyano- CF 0 H CH2CH2OH alkyl group can beprepared by substituting 3- series 3, vol. 11, page 211.

Compounds having the general formula:

ethyl-aniline for aniline or meta-toluidine in the wherein X. stands.-for hydrogen or methyl. and

Rihas; the.- meaning previously assigned. to it. The preparation ofthese-latter compounds is well known.

N-ethyZ-3-ethylam'line grams of 3-ethylaniline, 50 cc. of ethanol and 1:gram. of Raney: nickel are. heated together in a: shaking autoclave for24 hours at 210- C. The reaction mixtures is: then cooled; filtered anddis.- tilled" under reduced pressure. A. 90% yield of: N-ethyl3-ethylaniline is. obtained.

By the: substitution of an equivalent amount.

of methanol, normal propyl' alcohol, isopropyl: alcohol, normal butylalcohol, isobutyl alcohol, secondary butyl alcohol and normal. amyl'alcohol'; for example, for-ethanol in the above example- [N'-'-methyl-,N'-n-propyl'-, N'-isopropyI-, N n-bu tyl-. N-isobutyl-, N-secondarybutyland N'-n-- amyl-l- 3.-ethylaniline., respectively, are obtained.

N -B-hydro:z:yethyl-S-ethylaniline This. compound can. be. preparedbyreacting 3,-ethylanilinewith ethylene oxide (preferably-in: excess)-ina. closed, reaction vessel at atemperature. of about. 150 C.-160 C.for 6. hours. The reaction mixture isdistilled under reduced pres--vsure to obtain the desired. product.

Nrc-hydroxypropyl-3-ethylaniline and N-'y -hy-'droxypropyl-3-ethylaniline, for example, canbe; obtained by substitutingpropylene oxide and trimethylene oxide, respectively, for ethylene oxidein the above reaction and proceeding in a substantially similar manner.

N-allcyl;.N hydrcxyallcyl methylaniline compounds These compoundsv canbe obtained by treating an N-alkyl-3-ethylaniline. compound prepared.for example as indicated above with. an. alkylene. oxide, such as thosementioned. hereinbefjore. These compounds can likewise be obtained byusing. an alkylene halohydrin. in place of an alkylene oxide. Thusethylene chlorohydrin, alpha propylene chlorohydrin, beta, propylenechlorohydrin. and, trimethylene chlorohydrin. can be. used to introducethe B-hydroxyethyl, thefl-hydroxypropyl, the CHsCHCHOH and thevhydroxypropyl group,. respectively. The. 3,: -dihydroxypropyl group canbe introduced into the nitrogen atom. by treatment with CICHzCHOI-I-C'HzOH l-chloropropandiol) The N-alkyl, N-hydroxyalkyl-3-ethylanilinecompounds. can also. be. prepared. by first. formingthe,N-hydroxyalkyl-3:-ethylaniline compound and: alleylating. to.introduce the desired. alkyl group on. the nitrogen atom.

N-carbalkoruaZlm/L. N-hydroxualkyl-3.-- ethylam'line compounds These.compounds. can. be prepared. by treating Ni-hydroxyalkyl-3-ethylanilinecompounds with. compounds.- such. as methyl acrylate,. ethyl. acrylate,methyl crctonate. and ethylv crotonate. in-

e. the presence of a smallv amount of acetic. acid, to introduce the.133. and.

-ouomoooo=n,

group, respectively, into the nitrogen atom. The

reaction can be carried. out by heating thev substances. indicated on.a. steam bath until the reactiorr is. completa. e. g.. 7.2v to hours,and recovering. the..- desired: compound by distillation under-reducedpressure,.e. g; a pressure of 1-:10 mm. The. grouping --CH2 COO= alkylcan be introduced into the nitrogen atom in accordance with the.procedure described in the prior act. (See Beilstein, volume 12, pages468 to 474, inclusive; Berichte. der Deutschen. Chemischen-Gesellschaft, vol. 8, pages 1156 and 1157 (1875).; J.. Braktische.Chemie,v vol. 38, pages 436 and. 437, and.ComptesRendusvol. page 126)N-cyanoaZkyl; N -h'ydroxyalkyl-3-ethylanilinecompounds These: compoundsvcan? be. prepared by reacting. a. nitrilei compound such. asacrylonitrile, ocmethyl acrylonitrileor crotononitrile with an N-hydroxyalkyl-3Fethylaniline. compound.

N hydroxyalkyl-3=ethy1aniline compounds, respectively can. be obtained;

N-methowyethul-3+ethylanilinc This-compound; can be prepared by reacting3- ethylaniline with ethylene glycol monomethyl ether in the presence ofRaney nickel in an autoclave; for. about 10v hours at. a temperature ofapproximately 225 C. Other N-alkoxyalkyl radicals: can be introducedinasimilar manner. To illustrate, ethylene glycol mcnoethyl ether can be-used: in place of ethylene gl'vcol monomethyl. ether to introduce the-CH2CI-I'2OC2H5 radical on the nitrogen atom. Hydroxyalkyl groups can beintroduced into the N-alkoxyalkyl-3-ethylaniline compounds to formN-alkoxyalkyl-Nhydroxyalkyl-3-ethylaniline compounds;

Preparation. of o.-chloro-benzotrichloride A stream. of chlorine wasbubbled into a flask containing 5010; grams of o-chloro-toluene at C.until; an increase in. weight of 400 grams was obtained. During the.addition which requiredabout. 80* hours. an ultra-violet lamp was placednext: totheilask, thatis; the reaction was carried out underultra-violet light. The reaction mixture resulting was distilled througha Fenske. column. under reduced pressure and. that fraction whichdistilled over at 135 138 CV19 mm. consisted substantially. ofo-chloro-benzotrichloride. An analysis. of. this fraction for chlorinedisclosed. that, it contained, 59.45% chlorine, whereas, thetheoreticalamount of chlorine for o-chloro-benzotrichloride is. 62.0 1-

The. preparation oi this; compound. is referred to. in. the; Journal ofthe. American Chemical Societyc vol... 57,. page. 2066. (4935i whereinthegrams of sublimed antimony trifluoride were:

placed in a distilling flask and the mixture was heated until reactionhad set in. At this point heating was discontinued temporarily since thereaction is exothermic and heat was applied to the reaction mixture onlyas necessary to carry it to completion. During the reaction the desiredproduct is distilled from the reaction vessel and recovered in asuitable vessel. The distillate thus obtained was washed with 6 Nhydrochloric acid and then dried over CaClz. When distilled through aFenske column 130 grams of o-chlorobenzotrifiuoride boiling at 149-150C. at '760 mm. were obtained. The yield is 80% of the theoreti-- cal.The use of pure sublimed antimony trifluoride has been found quiteessential to the proper carrying out of the above-described reaction.

The preparation of o-chloro-benzotrifluoride is likewise disclosed inthe Journal of the American Chemical Society, vol. 57, page 2066 (1935).

Preparation of 2-chlOro-5-nitro-benzotriflaoride 225 grams of fumingnitric acid and 336 grams of concentrated sulfuric acid (95-96%) weremixed together and then cooled to 7 C. 198' grams ofo-chloro-benzotrifiuoride were then added dropwise with stirring over aperiod of 2 hours while keeping the temperature between 5-10 C. Thereaction mixture was stirred for one hour at C. and for an additionalthree hours at room temperature following which it was poured into threeliters of ice and water. The white precipitate formed by this treatmentand which melts at 27-28 C. was extracted with chloroform, washed withdilute aqueous sodium bicarbonate solution and then distilled under re-'duced pressure. 2-chloro-5-nitro-benzotrifluoride boiling at 85-87 C./2mm. is obtained. The yieig was 233 grams or 94% of the theoretical y ePreparation of 2-aminO-5-nitro-benaotrifluoride 58 grams of2-chloro-5-nitro-benzotrifiuoride-, 600 cc. of ethanol and 102 grams ofliquid ammonia were heated together for eight hours at 120-125 C. in ashaking autoclave. The reaction mixture was then removed and the ethanoldistilled off under reduced pressure. 400 cc. of water were added to thesolid remaining after the distillation and after stirring the mixturefor thirty minutes, it was filtered and the precipitate obtained Washedwith water and dried. The precipitate consisted primarily of2-amino-5-nitrobenzotrifluoride having a melting point of 80-88 C. Theyield was 40 grams 'or 75% of'the theoretical yield. Upon purifying theproduct by crystallization from methyl alcohol, 2-amino-5nitro-benzotrifluoride melting at 9092 C. was obtained.

Preparation of 2-amino-3-chloro-5-nitro-benzm trifluoride 20.6 grams of2-amino-E-nitro-benzotrlfiuoride were dissolved in 30 cc. of warmconcentrated sulfuric acid (9596%) and then precipitated as a finesuspension by pouring into a 500 cc. 3-neck flask containing 250 cc. ofcold water. One gram of FeCl: was added and chlorine was bubbled in atroom temperature for four hours while stir-'- ring. A sintered glasstube was used for the chlorine addition and the reaction was run under aslight pressure head. The reaction mixture ob-- tained was filtered andthe precipitate-thereby recovered was washed first with aqueous NaI-ISOa solution and then with water and dried. A yield of 12 grams or50% of the theoretical yield of 2-amino-3-chloro-5-nitro-benzotrifluoride having a melting point of 107 to109 C. was obtained.

Similarly, 2-amino-3-bromo-5-nitro-benzotrifluoride can be prepared byreacting 2-amino.-5- nitro-benzotrifiuoride with bromine following thegeneral procedure described in the foregoing example.

Preparation of 2-amino-3-iOdo-5-nitro-ben2otrifluoride Preparation of2-amino-3-fluoro-5-nitro-benzotrifluorz'de This compound can be preparedby the use of 2-chloro-3-trifluoromethylaniline as a starting material.1-fluoro-2-chloro-3-trifluoromethylbenzene is first prepared andnitrated to obtain 1-fiuoro-2-chloro-3-trifluoromethyl 5-nitrobenzenefrom which 2-amino-3-fluoro-5-nitrobenzotrifluoride is obtained byamination. The preparation of these compounds is described hereinafter.

Preparation of methylbenzene 19.6 grams (0.1 gram mole) of2-chloro-3-trifiuoromethylaniline are diazotized, after stirring into amixture of 150 cc. of water, grams (0.3 gram mole) of concentratedhydrochloric acid and sufficient ice to maintain a temperature of 0 to 70. throughout, by adding a solution of 8 grams (0.113 gram mole) of 98%sodium nitrite in 15cc. of water very rapidly below the surface in orderto prevent loss of nitrous acid. Diazotization is complete when a fainttest for nitrous acid on starch potassium iodide test paper lasts for 20minutes. The diazo solution is filtered to remove a small amount ofimpurities.

While the diazotization is in process 6.8 grams (0.11 gram mole) ofboric acid are dissolved in 20 grams (0.4 gram mole) of hydrofluoricacid in a lead beaker (a paraflin coated glass beaker may also be used)keeping the temperature below 25 C. The solution is cooled to 5 C. to 10C. and is then ready for use.

The ice cold fluoboric acid (HBF4) solution is added to the diazoniumsolution prepared asdisclosed above at a fairly rapid rate, therebycause ing the precipitation of a thick gray paste of 2-chloro-3-trifluoromethyl benzene diazonium borofiuoride. This paste isstirred for 30 minutes and then filtered. The solid recovered byfiltration is washed with cc. of water, 50 cc. of ethyl alcohol and thenwith 50 cc. of ether. Between the washes just mentioned, the precipitateis sucked as dry as possible and following the final washing, is spreadout to facilitate evap'o ration of the residual ether.

Upon cooling the reac-' The dry solid obtained as disclosed above isplaced in a distillation flask and decomposed by heating with a flame atthe top edge of the solid. The decomposition thus begun is permitted tocontinue by itself as long as it will and then heated again. By thismeans the borofiuoride is soon quietly decomposed with the evolution ofnitrogen and boron trifluoride. The desired compound 1fluoro-2-chloro-3-trifiuoromethyl benzene is distilled from the tarryresidue under reduced pressure and purified by redistillation underreduced pressure. A reduced pressure of 2 to 10 mm'., for example, issatisfactory.

Preparation of 1 fluoro-Z chloro 3 triflaoromethyl-5-nitro benzene 25grams of l-fiuoro 2 chloro 3 trifiuoromethyl benzene are dissolved in150 cc. of concentrated sulfuric acid (specific gravity 1.84) and theresulting mixture is cooled to C. 20 grams of fuming nitric acid in 50cc. of concentrated sulfuric acid (specific gravity 1.84) are then addedslowly. The reaction mixture resulting is then slowly warmed to 50 C.and after a short time poured onto ice. A yellowish precipitatel-fiuoro- 2-chloro-3-trifiuoromethyl nitro benzene, is formed and isrecovered by filtration, washed with water and dried.

Preparation of 2 amino-3-fluoro-5-nitro benzetrifluoride 25 grams ofl-fiuoro 2 chloro 3 trifiuoromethyl-5-nitrobenzene are placed in anautoclave together with 250 cc. of concentrated aqueous ammonia, warmedto 120 C. for hours and then cooled. The reaction mixture is filteredand the precipitate obtained upon filtration is washed with water anddried. The precipitate consists of2-amino-3-fluoro-S-nitro-benzotrifiuoride. It may be purified, ifdesired, by crystallization from acetic acid.

Preparation of l-amino-4-nitro-2,6-di-trifiuoromethyl benzene Thiscompound can be prepared by following the reactions described inconnection with the preparation of2-amino-3-chloro-5-nitro-benzotrifiuoride but starting withl-chloro-2,6-dimethyl benzene instead of o-chloro toluene. The finalchlorination reaction involved in the preparation of2-amino-3-chloro-5-nitro-benzotrifiuoride will of course be omitted.1-chloro-2,6-ditrichlorom'ethyl benzene; 1-chloro-2,6-di-trifluoromethylbenzene; 1-chloro-4-nitro-2,6-di-trifluoromethyl benzene and1-amino-4-nitro-2,6- di-trifluoromethyl benzene, respectively, areobtained.

.The azo compounds of my invention may be advantageously directlyapplied to the textile material undergoing coloration in the form of anaqueous suspension which can be prepared by grinding the dye to a paste,in the presence 'of;a sulfonated oil soap, or other suitable dispersingagent and dispersing the resulting paste in water. Direct dyeingoperations can, with advantage, be conducted at temperatures of about 60C. to 85 0., but any suitable temperature may be used.

Thus, the textile material to be dyed or colored is ordinarily added tothe dyebath at a temperature lower than that at which the main portionof the dyeing is to be efiected, e. g. a temperature of from 45 to 55 C.Following this the temperature is raised to that selected for carryingout the operation. The temperature at which the process is carried outmay vary somewhat, depending upon the particular material undergoingcoloration. As understood by those skilled in the art, the intensity ofdyeing can be varied by varying the proportion of dye to the materialundergoing preparation. Generally speaking, 1 to 3 per cent by weight ofthe dye to material is employed, although any desired proportions can beused.

Suitable dispersing agents are disclosed in U. S. Patent 2,115,030,issuing April 26, 1938. The process disclosed in the aforesaid patentfor the dyeing of cellulose acetate can be used in applying the dyes ofthe present invention to cellulose acetate. While a satisfactory methodfor dyeing has been disclosed herein, it will be understood that anyother suitable methods for dyeing the non-vegetable textile materialsnamed herein can be employed. Lacquers may be colored with the dyecompounds of my invention by the methods customarily employed in thelacquer art.

The term nylon is intended to describe a linear polyamide resin such asset forth in the United States Patent 2,071,250, dated February 16,1937.

What I claim is:

1. The azo compounds having the formula:

wherein R. stands for a CnH2nCO0CmH2m+l group wherein m stands for anumber selected from 1 and 2 and n stands for a number selected from 1,2 and 3 and R1 stands for a hydroxyalkyl group hav ing 2 to 5,inclusive, carbon atoms and wherein said hydroxyalkyl group containsfrom 1 to 2 hydroxy groups and has less hydroxy groups than carbonatoms.

2. The azo compound having the formula:

CF; /CH2CH2COOCH5 CHzCHgOH Fa 02H:

JOSEPH B. DICKEY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,153,018 Heyna et al. Apr. 4,1939 2,194,926 Daudt et a1 Mar. 26, 1940 2,194,927 Daudt et a1. Mar. 26,1940 2,231,707 Dickey et a1 Feb. 11, 1941 2,273,700 McNally et al Apr.17, 1945 2,391,179 McNally et a1. Dec. 18, 1945

